Boat centering device



May 22, 1962 P. A. BROSCH BOAT CENTERING DEVICE 2 Sheets-Sheet 1 FiledFeb. 8, 1960 INVENTOR. PRlNGLE A. B OSCH Ze m ATTORNEYS May 22, 1962 P.A. BROSCH BOAT CENTERING DEVICE 2 Sheefis-Sheet 2 Filed Feb. 8, 1960 m Qv3 We INVENTOR. PRINGLE A. BROSCH ATTORNEYS United States Patent ()ffice3,035,723 Patented May 22, 1962 3,035,723 BOAT CENTERING DEVICE PringleA. Broseh, 3185 S. Arlington St., Akron, Ohio Filed Feb. 8, 1960, Ser.No. 7,169 2 Claims. (Cl. 214-84) The present invention relates to boattrailers. More particularly, the invention relates to an improved devicefor simplifying the loading of a floating boat onto a trailer.Specifically, the invention relates to an improved device for centeringthe boat on the trailer while it is being loaded.

As boating has become a more and more popular sport, trailers used totransport boats overland have been made available under a wide varietyof constructions. Boating enthusiasm has become widespread and theweekend sailor can be found in all walks of life. He may not wish to paya yearly docking fee, or he may wish to enjoy the waters of variouslakes and rivers which are not navigabiy connected. The boat trailer isthe result. Whereas the boat trailer first found wide acceptance intransporting only the lighter boats, eventually larger and heavier boatswere docked on trailers at the place of the owners residence andtransported thereon to the locale of the lake, river or other site wherethe boat was launched for the days outing.

With the increase in the size of the boats so used came attendantproblems, the solution to which lay in improved trailer construction.One such problem is the difficulty encountered in centering the boatpreparatory to loading. That is, aligning the longitudinal axes of theboat and the trailer so that the keel of the boat will position withinthe range of the keel guides as the boat is brought out of the wateronto the trailer.

A variety of keel guides are presently available which are used tocenter the boat during the loading operation.

One such guide is constructed in a spool-like configuration with acentral portion of relatively small diameter and of a width to snuglyaccommodate a keel between the substantially radial surfaces that definethe central portion and which taper divergently away from the centralportion, terminating in the cylindrical ends of the roller.

Another known guide roller is constructed with the configuration of aV-shaped pulley.

Another known keel guide is constructed by mounting three rollers at therearmost end of the longitudinal frame member. When these rollers aremounted on a common shaft the center roller is of a smaller diameterthan the two outer rollers. Another configuration utilizing threerollers has the three rollers mounted on separate shafts. These shaftsare angularly disposed to each other so that the surface of the rollersprovides a troughlike guideway for the keel. When three shafts are usedthe diameter of the rollers may be uniform.

All of these configurations are satisfactory for boats of light weightwhich can be easily maneuvered from the shore, dock or loading rampwhile the boat is free floating. However, heavier boats are more arduousto maneuver, even in calm or still water, and when their handling isencumbered by choppy water, a current or a surface breeze it becomespractically impossible to direct the keel into the narrow confines ofany of the prior art keel guides and thereby center the boat withrespect to the trailer.

It is therefore an object of the present invention to provide animproved boat centering device and keel guide.

It is a further object of the present invention to provide an improvedkeel guide which, though it may be initially contacted by the boat keelto either side of the center thereof, it will, by the continued forwardmotion of the boat transfer the keel to the center thereof.

It is a still further object of the present invention to provide animproved boat centering device which operates by guiding the keel towardthe center without applying pressures directly against the hull,irrespective of the shape of the hull.

It is a still further object of the present invention to provide animproved keel guiding boat centering device which will transport thekeel of the boat from either end thereof to the center, whilemaintaining that portion of the keel in contact therewith insubstantially the same horizontal plane.

It is a still further object of the present invention to provide animproved keel guiding boat centering device which can be as readilyadapted to be mounted on a dock as on a trailer.

It is a still further object of thepresent invention to provide animproved boat centering device which is easy to operate and economicalto construct.

These and other objects of the invention, as well as the advantagesthereof, will be apparent in view of the following detailed descriptionand the attached drawings.

In the drawings:

FIG. 1 is a plan view of a boat trailer equipped with the improved boatcentering device;

FIG. 2 is a side elevation of the boat trailer depicted in FIG. 1;

FIG. 3 is an enlarged partial plan view of that portion of the trailerdepicted in FIG. 1 on which the improved boat centering device ismounted showing the device in greater detail;

FIG. 4 is an enlarged partial rear elevation of that portion of thetrailer depicted in FIG. 3 with the boat centering device partially cutaway; and

FIG. 5 is a partially cut away cross section taken substantially alongline 5-5 as indicated in FIG. 4.

A boat centering device according to the invention is generally in theshape of an elongated cylinder having two cylindrical heliclines, onewith a left and the other with a right hand spiral, placed top to topand terminating in a common circumferential groove. The heliclines areformed by spiral or helicoidal grooves formed in the outer surface ofthe cylinder. The width of a groove is of suflicient dimension tostraddle the keel. The depth of the groove is of such a dimension thatthe weight of the boat rests on the device through the keel and notdirectly through the hull. The width of the raised portion between thegrooves is of suflicient dimension to oifer a lateral thrust against thesides of the keel to move the boat axially along the device to thecenter thereof as the boat rides longitudinally forward upon the device.The concept herein disclosed is of sufliciently universal applicationthat large pleasure craft can be centered by a device constructedaccordingly. When the device is used to center such heavy craft theposition of the device with reference to the surface of the water isregulated so that the buoyancy of the water carries the major portion ofthe weight of the boat while it is being forced into centered position.Thereafter the keel rides in the central circumferential groove as theboat loading operation is completed.

Referring now to FIGS. 1 and 2, the improved centering device,designated generally by the numeral 10, is operatively mounted on a boattrailer, indicated generally by the numeral 11. The trailer 11 comprisesa longitudinal frame member 12, which may be of box construction asshown in FIG. 4, to which is affixed a suitable transverse frame member13, as by welding 14. A suspension system (not shown) is interposedbetween the axle 15 and the transverse frame member 13 to assist thepneumatic tire assemblies 16, mounted on axle 15, in reducing thedamaging road shocks which would otherwise act on the trailer and boatcarried thereon.

Torque rods 17 interconnect the forward portion of longitudinal framemember 12 to the laterally outer portions of axle 15 to lend stabilityto the trailer. These torque rods 17 may be bolted, as by bolts 18, tothe frame member 12 and connected to the axle 15 by suitable means notshown.

A trailer hitch 19 is mounted on the forwardmost end of the longitudinalframe member 12 so that the trailer may be conveniently attached to acar or other towing vehicle.

A bow block 2!) is secured to an upright post 21 which in turn isalfixed to frame member 12 in proximity to the forward end thereof. Asbest seen in KG. 1 the bow block is V-shaped to suitably engage the bowof a boat loaded on trailer 11.

Positioned between how block 29 and hitch 19 a Winch 22 is mounted onstanchion 23. Stanchion 23 is fixed to frame member 12, as by welding24, and is of suflicient height that winch 22 can be eifciently employedto draw a boat onto the trailer 11. By drawing the boat firmly againstbow block 20 and then locking winch 22 the boat is secured againstfurther longitudinal movement fore or aft and is ready to betransported.

To facilitate loading the boat with the winch 22, a series of mediallypositioned keel supporting means or keel rollers 25 is positioned alongthe longitudinal frame member 12 medially of the bow block 2% and thecentering device 10. The keel rollers 25 are journaled in gudgeons 26attached to frame member 12, and are preferably of a spool-likeconfiguration. That is, the central portion 27 and the end portions 28are cylindrical but the diameter of the central portion 27 issubstantially smaller than the diameter of the end portions 28. Thewidth of the center portion 27 is sulficient to accommodate a keel andis connected to the end portions 28 by divergently outward taperingsurfaces 39. However, rollers 25 could also be of a cylindricalconfiguration.

To further facilitate the loading operation and to lend support andstability to the boat in transit cylindrical hull rollers 32 and 33 arejournaled on gudgeons 34 and 35, respectively, which are suitablyattached to transverse frame member 13.

A second transverse frame member 36 is affixed to the longitudinal framemember 12 at the rearmost end thereof. In proximity to the outer ends ofmember two more hull rollers 37 and 38 are journaled in adjustablegudgeons 39 and 40, respectively. Rollers 37 and 38 assist the loadingoperation in a manner similar to rolls 32 and 33 hereinbefore describedand also assist in stabilizing the boat in transit by supporting aportion of the hull, or, depending on the length of the boat, thetransom.

As can be best seen in F168. 3, 4 and 5, angle brackets 41 and 42 areattached to the web 43 of channel member 36, as by a plurality of bolts44 passing through bores 45 on the vertically disposed web 43 whichregister with bores 46 on the vertical leg 47 of angle brackets 41 and42. The horizontal leg 48 of both brackets 41 and 42 is provided with aslot 49 whereby a bolt 50 may be used to adjustably position angledgudgeons 51 and 52 longitudinally. Gudgeons 1 and 52 journal the coreshaft 53 of device 10 so that it is freely rotatable. It is preferredthat the ends 10:? of the centering device adjacent the gudgeons 51 and52, be crowned (as best seen in FIG. 4) to reduce or minimize lateralfriction during loading of a boat.

The centering device 16 can be made from rubber, neoprene or othersuitable material 54 which is shown to be bonded to shaft 53, out thedevice may be made in the form of a sleeve that is rotatable about theshaft 53. The concept of the invention merely requires that thecylindrical heliclines 55 and 56 be freely rotatable.

The heliclines 55 and 56 themselves are most aptly described as beinglikened unto an axially expanded Acme thread. That is, the heliclines 55and 56 have a similar cross sectional profile, with crests 57 and roots58 and angularly disposed faces 59 interconnecting the crests 57 and theroots 58, but they are axially expanded in that the crest 57 profiledimension is not equal to the root 58 profile dimension and the threaddepth dimension (the vertical dimension from the crest 57' to the root53), but rather the root 5% dimension exceeds the crest 57 dimension. Instandard thread design these dimensions would all be equal to one halfthe pitch, ergo, an expanded Acme thread. 7

Continuing the use of the analogous thread terminology, helicline 55 isformed as a right hand thread and helicline 56 as a left hand thread.The two heliclines 55 and 56 terminate in an annular groove 6%, thediameter of which is preferably smaller than the root diameter of theheliclines 55 and 56 and is of such a width as to guidingly embrace thekeel 61 attached to the hull 62 as shown in FIG. 4. The sides 63 and 64connecting the heliclines to the recessed annular groove 6% arepreferably slightly divergently outwardly tapered from said groove 69 tominimize friction against the device from the sides 65 of keel 61.

The operation of the centering device 10 would be as follows. Assume thekeel 61 first contacts the device if at 61a, shown in phantom in H6. 4.Since initial contact is made near the bow, the hull 62a is narrowerthan that portion of the hull 62 shown as representative of the positionit assumes when the keel 61 is centered or when the boat is loaded. Ofcourse, the keel 61 could land on the fiat surface of a crest 57, but asthe Winch 22 is turned to draw the boat onto the trailer 11 the keel 61,by the frictional contact with the crest 57 would rotate the device 1i)and the keel 61 would drop into root 58 as at 61a. Continued turning ofthe winch 22 continues the rotation of the device '11 by the frictionalcontact of the keel 6 1 with root 58. The hand of the heliclines 55 and55 guides the keel 61 transversely inwardly toward the annular groove 60which is at the centered position, and in which the keel 61 remainsduring the remainder of the loading operation. If desired the roots 53may be knurled to increase the friction available thereagainst when theboat being loaded initially contacts the device 10.

It is now apparent that the applicant has provided a novel, new anduseful device whereby the keel of a boat may be automatically alignedwith a predetermined axis as the boat is drawn across the device.

What is claimed is:

1. An improved cylinder device for centering a boat keel, said cylinder54 having a profiled surface and an axially extending mounting shaft 53,comprising, an annular groove 60 around the center of said cylinder,said groove having a substantially flat root profile and conicallytapered sides 63, 64 intersecting said cylinder surface, opposite handheliclines 55, 56 on either side of said groove, each said heliclinebeing defined by a continuous root 58 having a substantially flatprofile intersecting said groove sides 63, 64 radially inward thecylinder surface and a continuous crest 57 having a substantially fiatprofile coextensive with said cylinder surface and intersecting saidgroove sides 63, 64 at the cylinder surface, each said helicline rootand crest being connected by angularly disposed faces 59, the diameterof said groove root being smaller than the diameter of the heliclineroots, the width of each said helicline crest being sufiicient toprovide lateral thrust against the side of a boat keel to move said keelaxially into said center groove.

2. A boat trailer comprising; a trailer frame; wheels supporting therear of said frame; a towing attachment at the forward extremity of saidframe; a rotatable cylinder mounted on said frame for centering a boatkeel medially of said frame, said cylinder having a profiled surface, anaxially extending mounting shaft, an annular groove around the center ofsaid cylinder, said groove having a substantially flat root profile andconically tapered sides intersecting said cylinder surface, oppositehand heliclines on either side of said groove, each said helicline beingdefined by a continuous root having a substantially flat profileintersecting said groove sides radially inward the cylinder surface anda continuous crest having a substantially fiat profile coextensive withsaid cylinder surface and intersecting said groove sides at the cylindersurface, each said helicline root and crest being connected by angularlydisposed faces, the diameter of said groove root being smaller than thediameter of the helicline roots, the width of each said helicline crestbeing sufficient to provide lateral thrust against the side of a boatkeel to move said keel axially into said center groove; 2. forward keelroller mounted medially on said frame forwardly of said cylinder andmeans for drawing said boat forwardly over said cylinder and saidroller.

References Cited in the file of this patent UNITED STATES PATENTS1,095,445 Alvey May 5, 1914 1,405,316 Napier Jan. 31, 1922 2,377,431Lasko June 5, 1945 2,630,904 Bozek Mar. 10, 1953 2,805,786 Green Sept.10, 1957 2,965,252 Morsch Dec. 20, 1960

